This invention relates in general to commercial vehicle wheels and in particular to dual cast or forged commercial vehicle wheels having spokes.
It is known to mount vehicle wheels upon axle hubs having threaded studs projecting therefrom. The studs extend through apertures formed through a wheel hub and receive wheel nuts to secure the wheels upon the axle hubs. The mounting system may be used to mount a single wheel upon an axle hub, as is the case for automobiles, or a pair of wheels upon a single axle hub, as is commonly used upon commercial vehicles, such as trucks. For a tractor trailer combination truck, dual wheels are typically mounted upon the driven rear wheels of the tractor and upon the axles of the trailer to distribute the weight of the load. When a pair of wheels are mounted upon a single axle hub, the structure is commonly referred to a dual wheel arrangement.
In a dual wheel arrangement, the inner and outer wheels are typically identical with one of the wheels reversed relative to the other wheel. Each wheel includes a wheel disc that extends across the end of an annular wheel rim to allow room within the wheel rim to receive the axle hub and a wheel brake mechanism. The wheel rim is designed to carry a pneumatic tire while the wheel disc typically includes a central hub supported within the wheel rim by a plurality of radially extending wheel spokes. The wheel hub has a plurality of stud-receiving apertures formed therethrough. The apertures are equally spaced about a bolt hole circle with the number of apertures increasing with the size of the wheel. The facing central portions of the wheel discs are flat and designed to contact one another when the wheels are mounted upon the axle hub. The remainder of the disc and the spokes that extends from the central portion to the wheel rim are typically dished.
Prior art wheel discs are typically stamped out of steel and welded to the inner surface of the wheel rim. The steel provides strength while allowing the wheel discs to be made thin enough to permit mounting dual wheels upon an axle hub while maintaining sufficient stud engagement length for the wheel nuts.
In order to reduce the unsprung wheel weight while also allowing for esthetic wheel design, it would be desirable to provide commercial vehicle wheels cast or forged from aluminum alloys or other light weight metals or alloys. Such wheels would include a central wheel hub supported within a wheel rim by a plurality of radially extending wheel spokes. However, to provide sufficient strength, the wheel spokes need to be relatively thick. Furthermore, cast or forged wheel hubs tend to have relatively the same thickness as the wheel spokes. While single cast or forged wheels may be utilized, the doubling of the hub thickness with a dual wheel mounting arrangement may not provide sufficient stud engagement length for the wheel nuts. Accordingly, it would be desirable to provide a design for cast or forged commercial vehicle wheels that would be adaptable for a dual wheel mounting arrangement.